478 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
and it rises in a more or less triangular form to a height of 0:4 of an inch, 
The spine is 0:7 of an inch in length, 0:15 of an inch wide at the base, and tapers 
to a point; it is smooth, slightly curved backwards, is somewhat acutely angular 
along the anterior margin, and has a groove posteriorly for the attachment of 
the fin. The anterior spine is placed immediately above the twentieth vertebra 
from the occiput. The spine of the posterior fin is over the fifty-first vertebra, 
and 8°3 inches behind the anterior one; it is 1°1 inches in length, similar in 
form to the anterior spine, except that it is considerably more curved, and, 
in proportion to its length, more slender. The second fin is larger than the 
first in proportion to the length of the spine. Anal fin not exposed. The 
caudal fin is large, the upper lobe supported by the vertebral column; it is 
2:5 inches in length. The lower lobe is 11 inches in length, and its greatest 
diameter is 1:0 inch. 
The pectoral fins are large and powerful. The anterior margin is 2°5 inches 
behind the snout; it is 1:3 inches in length, and extends 1:2 along the abdominal 
surface; like the remainder of the body and other fins, they are thickly coated 
with dermal ossicles. The ventral fins are situated 2°8 inches behind the 
anterior base of the pectorals; the base extends 0-9 of an inch along the surface, 
and the anterior margin is 0°8 of an inch in length. 
Formation and Locality.—Upper Cretaceous: Sahel Alma, Mount Lebanon. 
Ex coll_—Lewis Collection, British Museum. 
Genus. Centrophoroides. Davis. 
Body elongated; dorsal fins armed with short spines, deeply embedded; 
vertebree equal in height and length; mouth inferior. Teeth unicuspidate, 
different in the two jaws, maxillary teeth lanceolate and sharply pointed ; 
mandibular teeth broader, somewhat obtusely pointed. Skin covered with minute 
ossicles. 
Centrophoroides iatidens, Davis. 
(Pl. xv., figs. 2, 2a.) 
This specimen is imperfect: the snout and the caudal extremity are wanting. 
The part preserved exhibits the buccal orifice, the pectoral fins, and the length 
of the body as far as the second dorsal fin. It is 14 inches in length. The 
fish, when perfect, would probably be 18—20 inches in length; it is 2 inches in 
diameter between the pectoral fins. The head to the occiput occupies 2°8 inches ; 
to the pectoral arch 4 inches. The body is covered with dermal tubercles; they 
are triangular in outline, with striated surface, producing a serrated edge. 
